More precisely, the embodiments of the present invention relates to a device and a method for facilitating the operations of filling and sealing of the lighter. More particularly the present invention relates to a disposable lighter or a gas reservoir for all types of lighter of the type which comprises a reservoir made of plastic material, especially amorphous plastic, adapted to be filled with a liquid hydrocarbon, especially butane or mixtures of butane and other hydrocarbons.
Synthetic amorphous materials, like polymers such as ABS (Acrylonitrile Butadiene Styrene) or polycarbonate, often used for disposable gas lighters, are advantageous since they allow users to see the level of remaining fuel within the reservoir. However, such amorphous materials may be brittle as a result of their non-crystalline structure.
It is known in the art to arrange a well in the bottom of the reservoir and to insert a ball into the well. However, the force-fit introduction of the ball within the well can cause cracks in the well of the reservoir and thus create a leakage.
Other methods rely on the use of an 0-ring seal; however the cost effectiveness of such solutions is poor with regard to a definitive sealing feature.
U.S. Pat. No. 4,486,171 describes a method using a plug member molded integrally with the lighter body. This plug allows the filling of the body but the final closing and sealing of the reservoir is provided by the dispensing valve. Since such valve is force-fitted into the well, the risk of causing cracks remains.
There is therefore a need to improve known solutions relating to the operations of filling and sealing a transparent disposable gas lighter.